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mechanism (mĕk′ə-nĭz′əm)
n.
1.
a. A machine or mechanical appliance.
b. The arrangement of connected parts in a machine.
2. A system of parts that operate or interact like those of a machine: the mechanism of the solar system.
3. An instrument or a process, physical or mental, by which something is done or comes into being: "The mechanism of oral learning is largely that of continuous repetition" (T.G.E. Powell).
4. A habitual manner of acting to achieve an end.
5. Biology The involuntary and consistent response of an organism to a given stimulus.
6. Psychology A usually unconscious mental and emotional pattern that shapes behavior in a given situation or environment: a defense mechanism.
7. The sequence of steps in a chemical reaction.
8. Philosophy The doctrine that all natural phenomena are explicable by material causes and mechanical principles.
[New Latin mēchanismus, from Late Latin mēchanisma, from Greek mēkhanē, machine; see mechanic.]The American Heritage Dictionary of the English Language, Fourth Edition copyright 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.
mechanism (ˈmɛkəˌnɪzəm)
n
1. (Mechanical Engineering) a system or structure of moving parts that performs some function, esp in a machine
2. something resembling a machine in the arrangement and working of its parts: the mechanism of the ear.
3. (Mechanical Engineering) any form of mechanical device or any part of such a device
4. a process or technique, esp of execution: the mechanism of novel writing.
5. (Philosophy) philosophy
a. the doctrine that human action can be explained in purely physical terms, whether mechanical or biological
b. the explanation of phenomena in causal rather than teleological or essentialist terms
c. the view that the task of science is to seek such explanations
d. strict determinism. Compare dynamism, vitalism
6. (Psychoanalysis) psychoanal
a. the ways in which psychological forces interact and operate
b. a structure having an influence on the behaviour of a person, such as a defence mechanisSo, a mechanism can be a process. Natural selection is the process where one set of traits are selected over another set of traits.